题干

下列关于反应限度的叙述不正确的是(     )

A:反应限度是一种平衡状态,此时反应已经停止

B:达到平衡状态时,正反应速率和逆反应速率相等

C:达到平衡状态时,反应物和生成物浓度都不再改变

D:不少反应都具有可逆性,只是有的程度小,有的程度大

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A

同类题3

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    An elderly carpenter was ready to retire. He told his employer of his plans to leave the house building business and live a more leisurely life with his wife, enjoying his extended family. He would miss the pay check, but he needed to retire.

    The employer was sorry to see his good worker go and asked if he could build just one more house as a personal favor. The carpenter said yes, but in time it was easy to see that his heart was not in his work. He used shoddy materials to build the house. It was an unfortunate way to end his career.

    When the carpenter finished his work and the employer came to inspect the house, he handed the front-door key to the carpenter. “This is your house,” he said, “my gift to you.”

    What a shock! What a shame! If he had only known he was building his own house, he would have done it all so differently. Now he had to live in a home he hadn't built very well.

    It is the same with us. We build our lives in a distracted way, reacting rather than acting, willing to put up with less than the best. At important points, we don't give the job our best effort. Then with a shock we look at the situation we have created and find that we are now living in the house we have built. If we had realized that, we would have done it differently.

    Think of yourself as the carpenter. Think about your house. Each day you hammer a nail, place a board, or erect a wall, build wisely. It is the only life you ever build. Even if you live it for only one day more, that day deserves to be lived graciously and with dignity. The plague (牌匾) on the wall says, “Life is a do-it-yourself project.”

    Who could say it more clearly? Your life today is the result of your attitudes and choices in the past. Your life tomorrow will be the result of your attitudes and the choices you make today.

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同类题4

阅读下面的文字,完成文后各题。

古渡头

叶紫

    太阳渐渐地隐没到树林中去了,晚霞散射着一片凌乱的光辉,映到茫无际涯的淡绿的湖上,现出各种各样的色彩来。微风波动着皱纹似的浪头,轻轻地吻着沙岸。

    破烂不堪的老渡船,横在枯杨的下面。渡夫戴着一顶尖头的斗笠,弯着腰,在那里洗刷一叶断片的船篷。

    我轻轻地踏到他的船上,他抬起头来,带血色的昏花的眼睛,望着我大声说道:“过湖吗,小伙子?”

    “唔,”我放下包袱,“是的。”

    “那么,要等到明天啰。”他又弯腰做事去了。

    “为什么呢?”我茫然地,“我多给你些钱不能吗?”

    “钱?你有多少钱呢?”他的声音来得更加响亮了,教训似的。他重新站起来,抛掉破篷子,把斗笠脱在手中,立时现出了白雪般的头发,“年纪轻轻,开口就是‘钱’,有钱就命都不要了吗?”

    我不由得暗自吃了一惊。

    他从舱里拿出一根烟管,饱饱地吸足了一口,接着说:“看你的样子也不是一个老出门的。哪里来的呀?”

    “从军队里回来。”

    “军队里?……”他又停了一停,“是当兵的吧,为什么又跑开来呢?”“我是请长假的。我妈病了。”

    “唔!……”

    两个人都沉默了一会儿,他把烟管在船头上磕了两磕,接着又燃第二口。

    夜色苍茫地侵袭着我们的周围,浪头荡出了微微的合拍的呼啸。我的心里偷偷地发急,不知道这老头子到底要玩什么花头。于是,我说:“既然不开船,老人家,就让我回到岸上去找店家吧!”

    “店家,”老头子用鼻子哼着,“年轻人到底不知事。回到岸上去还不同过湖一样的危险吗?到连头镇去还要退回七里路。唉!年轻人……就在我这船中过一宵吧。”

    他擦着一根火柴把我引到船艘后头,给了我一个两尺多宽的地方。好在天气和暖,还不至于十分受冻。

    当他再擦火柴吸上了第三口烟的时候,他的声音已经和缓多了。我躺着,一面细细地听着孤雁唳过寂静的长空,一面又留心他和我谈的一些江湖上的情形,和出门人的秘诀。

    “……就算你有钱吧,小伙子,你也不应当说出来的。这湖上有多少歹人啊!……我欢喜你这样的孝顺孩子。是的,你的妈妈一定比我还欢喜你,要是在病中看见你这样远跑回去。只是,我呢?……我,我有一个桂儿。你知道吗?我的桂儿,他比你大得多呀!你怕不认识他吧?外乡人……那个时候,我们爷儿俩同驾着这条船。我给他收了个媳妇……”“他们呢?”

    “他们?那一年,北佬来,你知道了吗?北佬打了败仗,从我们这里过,我的桂儿给北佬兵拉着,要他做佚子。桂儿,他不肯,脸上一拳!我,我不肯,脸上一拳!……小伙子,你做过这些个丧天良的事情吗?……

    “小伙子!你看,我等了一年,我又等了两年,三年……我的儿媳妇改嫁给卖肉的朱胡子了,我的孙子长大了。可是,我看不见我的桂儿,我的孙子他们不肯给我……他们说:‘等你有了钱,我们一定将孙子给你送回来。’可是,小伙子,我得有钱呀!

    “结冰,落雪,我得过湖;刮风,落雨,我得过湖……

    “年成荒,捐重,湖里的匪多,过湖的人少,但是,我得找钱……

    “小伙子,你是有爹妈的人,你将来也得做爹妈的。我欢喜你,要是你真的有孝心,你是有好处的,像我,我一定得死在这湖中。我没有钱,我寻不到我的桂儿,我的孙子不认识我,没有人替我做坟,没有人给我烧纸钱……我说,我没有丧过天良,可是天老爷他不向我睁开眼睛……”

    他逐渐地说得悲哀起来,终于哭了,不住地把船篷弄得呱啦呱啦地响;他的脚在船舱边下力地蹬着。可是,我寻不出来一句能够劝慰他的话,心头像给什么东西塞得紧紧的。

    外面风浪渐渐地大了起来,我翻来覆去地睡不着,他也翻来覆去地睡不着。

    可是,第二天,又是一般的微风,细雨。太阳还没有出来,他就把我叫起了。他的脸上丝毫看不出一点异样的表情来,好像昨夜间的事情,全都忘记了。

    我目不转睛的瞧着他。

    “有什么好瞧呢?小伙子!过了湖,你还要赶你的路程呀!”

    离开渡口,因为是走顺风,他就搭上橹,扯起破碎风篷来。他独自坐在船艘上,毫无表情地捋着雪白的胡子,任情地高声朗唱着:

    我住在这古渡前头六十年。我不管地,也不管天,

    我凭良心吃饭,我靠气力赚钱!

    有钱的人我不爱,无钱的人我不怜!

……

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